I have concerns at deprecating regex with no plans to remove, for a very specific reason.

We are currently binding the C++ Standard to a very old ECMA Script Language Specification
that, AFIACT, was replaced by 5th edition in 2009 making our binding 14 years out of date by
the time we publish C++23. ECMA has continued to revise their standard, but ISO seems to
have fixed on that 5th Edition with ISO/IEC 16262:2011.

If we deprecate and neither remove nor revise our spec, this ancient binding is forever. As
the only reason we maintain that binding is for the regex grammar - that we modify anyway,
could we perhaps document that grammar entirely within our own standard, with a note to
meniton the ECMA Script Language Specification as the initial source of inspiration (hence
the name of the enumerator for that grammar)?

Note that I am not the regex expert to do that work, so not volunteering! But it is the kind
of concern I would like to see addressed before parking regex for an eternity in Annex D.

AlisdairM